1. Field of the Invention
The present invention relates to a facile method of applying a solid or flowable (aqueous or oil base) terrestrial delivery composition with one or more active insecticidal ingredients, with or without additional nontoxic ingredients, to control a variety of terrestrial (i.e., non-aquatic) insects or pests ((mainly insects and their close relatives (Arthropoda) as well as rodents (Muridae), nematodes, fungi, and weeds)) that are pests of ornamentals and turf, livestock, forest and shade trees, field crops and pastures, fruits and nuts, households, poultry, stored products, and vegetables with conventional ground or aerial techniques.
This invention further relates to a facile method of combining, mixing, encapsulating, agglomerating, or formulating one or more superabsorbent polymers with two or more active insecticidal or pesticidal ingredients, optionally with water, with or without various nontoxic adjuvants, diluents or carriers, etc., into solid powders, dusts, granules, pellets, extrusions or briquets, and/or into aqueous (or oil base) flowable, variable-viscosity sols or semi-gels. The use of superabsorbent polymers in this manner makes possible the mixing or application of insecticidal ingredients or pesticidal ingredients, with or without other additives, that would otherwise be difficult or substantially impossible to combine as joint- or multiple-action solid or flowable formulations.
The present invention also relates to a solid (i.e., powdered, extruded, flaked, granular, pelleted, briquetted) or variable-viscosity, flowable (i.e., sprayable, pumpable, injectable) terrestrial pest control delivery composition made from one or more solid superabsorbent polymers with or without water, and with one or more insecticidial agents, such as insecticides, ovicides, larvicides, pupicides, biological control agents, pathogens, parasites, microbial control agents, insect growth regulators, conventional toxicants, fumigants, systemics, chemosterilants, pheromones, attractants, repellents, or with one or more solid or liquid pesticidal agents such as acaricides, miticides, pesticides, herbicides, hormones, sterilants, bactericides, fungicides, nematicides, avicides, rodenticides, molluscicides, or predicides, or mixtures thereof, with or without one or more nontoxic adjuvants, diluents, or enhancers, such as carriers, baits, binders, deflocculating agents, fertilizers, penetrants, preservatives, spreading agents, surface-active agents, surfactants, suspending agents, wetting agents, stabilizing agents, compatability agents, sticking agents, waxes, oils, inverting oils, co-solvents, coupling agents, foams, antifoaming agents, synthetic plastics, elastomers, synergists, natural or synthetic polymers; and other additives and mixtures thereof.
In particular, the present invention is directed toward a method of formulating and applying one or more superabsorbent polymers with one or more insecticidal agent(s), and one or more pesticidal agent(s), with or without water or other additives, into solid powders, dusts, granules, pellets, extrusions, or briquets, or into flowable, variable-viscosity compositions such as sols or semigel-like formulations that can produce quick, slow, controlled, prolonged, or extended release of the active ingredients to simultaneously or concurrently control a variety of mature or immature terrestrial insects, and other non-insect pests in a variety of terrestrial habitats with a single application of a solid or flowable multi-product formulation.
Mode of action (e.g., fumigant, contact, slow-release, stomach poison, systemic, bait, etc.) will be dependent on the type(s) of insecticide(s), pesticide(s) and polymer(s) used in the solid or flowable compositions, the type of terrestrial habitat, and the species of insect(s) or pest(s) to be controlled. Release of the active agent(s) is via a polymer matrix water activation/swelling/diffusion mechanism and by environmental degradation of the polymer encapsulation matrix.
2. Discussion of the Prior Art
U.S. Pat. Nos. 4,400,391 and 4,401,456 disclose the use of alginate gel beads to encapsulate bioactive materials to provide for their controlled release. The patents describe beads being made to either float or sink (if used in an aqueous environment) and they may contain herbicides. These beads are also described as acting as carriers to place the bioactive material near the target species, for example, a floating bead containing a herbicide releasing the herbicide, in close proximity to floating aquatic weeds, or the beads falling through foliage to release herbicide into the soil.
U.S. Pat. No. 4,344,857 involves encapsulation by xanthate derivatives. The encapsulation techniques are complicated, costly and quality sensitive.
Gould et al U.S. Pat. No. 3,576,760, describes a method for entrapping fragrances, detergents, enzymes, food flavors and pesticides in a water soluble polymer. The entrapment is described as accomplished by mutually dissolving the water soluble polymer and the entrapped additive, which are then dried (e.g., spray dried). The primary purpose of this technique is to protect the entrapped species prior to target delivery. The polymers instantly dissolve in water and as such are unsuitable for controlled release. The technique is further limited in the types and quantities of entrapable compounds.
Mueller et al., U.S. Pat. No. 4,304,591, employs an allegedly novel free radical polymerized hydrogel. The ingredients are incorporated into the hydrogel primarily by presence in the polymerization solution, however some medicants are stated as suitably diffused into the matrix via a solvent medium thereafter. This method is limited in both the capacity of the hydrogel matrix and its ability to incorporate diverse, and potentially incompatible agents. The major effective use contemplated for this matrix is the delivery of medicants.
A U.K. Patent No. 2,108,517, discloses a hydrogel having at least one polymerizable cyclic (thio)ether and at least one hydrophilic homo-or co-polymer. This composition like Mueller et al. is stated as being particularly suited to slow release of medicants, particularly for treatment of tropical diseases.
A relatively new approach to insecticidal and pesticidal delivery has been by application of controlled-release formulations, to varying degrees of success, such as described by Richard W. Baker in Controlled Release of Biologically Active Agents, 1987, Wiley-Interscience Publishing, 279, pp. This text generally describes the use of various controlled release technologies including simple diffusion from monolithic devices such as hydrogels. However, this method is normally limited by hydrogel capacity and difficulties with incorporation of the desired agent, particularly hydrophilic substances. The capacity and incorporation problems with monolithic devices are often addressed by reservoir devices. More complex release mechanism include the use of biodegradable matrix carriers, namely, bonding of active ingredients in heterogeneously or homogeneously degradable polymers, called polyagents. Polyagents may actually be polymers formed of monomers of the active agent. The release mechanics of these controlled release mechanisms are complex, depending on the presence (and strength) or absence of degradable ligand bonds and their location (e.g., as active agent bonds to the polymer), concentration of the active agent and/or dispersant or solvent in the carrier, the relative hydrophobicity or hydrophilicity of the polymer, whether or not the polymer degrades homogeneously or heterogeneously, whether the active agent is in the solid form or liquid form in the polymer, etc. Further formation of such polyagents is complicated and often reagent specific.